The invention concerns an assembly forming a roller bearing, equipped with an information sensor device, comprising a magnetic pulse generator-encoder connected to a rotating part and a fixed sensor equipped with at least two sensitive elements capable of detecting these pulses.
Such assemblies, when equipped with a rotational speed sensor device, angular position sensor and/or direction of rotation sensor, can be used, in particular, for the wheels of automotive vehicles provided with an anti-lock system for said wheels. The information is then used by a computer-assisted braking system.
Roller bearings equipped with an information sensor device are already known. One of the problems posed with such bearings is their protection with respect to pollution from the surrounding environment, especially protection of the encoder that generates the magnetic pulses read by the sensor.
In the case of an information sensor device of the electric type, document EP-0 498 299 proposes that this problem be solved by using a pair of shutters, on one of which a phonic wheel is associated.
However, in addition to the fact that this assembly is not transposable to a technology of the magnetic type, it presents the drawback of requiring numerous parts for its implementation. Moreover, the flux concentrator is associated with the fixed collar, which complicates assembly by not isolating the rolling stress measurement function.
In the case of an information sensor device of the magnetic type, document EP-0 326 454 proposes a roller bearing assembly comprising a disk carrying the encoder that rotates in front of a sensor connected to another disk.
This assembly has the drawback of prescribing that the disk carrying the sensor is used to axially block the internal collar, which requires adequate dimensioning and materials. Moreover, arrangement of the sensor on this rigid disk requires an additional assembly operation that must be conducted precisely to obtain proper control of the air gap. The result is that this assembly is difficult to accomplish at the production rates in force in the automotive industry.
The invention seeks to remedy the drawbacks of the prior art by proposing an assembly that forms a roller bearing that is simple to assemble, while ensuring, on the one hand, effective protection of the bearing with respect to the surrounding environment and, on the other hand, proper control of the air gap. Moreover, the measurement function is totally dissociated from rolling stresses in the proposed assembly.
For this purpose, the invention proposes an assembly forming a roller bearing equipped with an information sensor device comprising a magnetic pulse generator-encoder and a sensor equipped with at least two sensitive elements capable of detecting these pulses, said assembly comprising:
a fixed spindle containing an axial bore;
a rotating external ring having an annular housing on the outside of the assembly that protrudes coaxially relative to said bore; and roller bodies arranged between this spindle and external ring; in which, in combination:
the encoder is connected on one lateral internal face of a plug that is arranged in the housing;
the sensor is arranged in the bore supported on an external lateral surface of the spindle, so that the sensitive elements are arranged facing each other and at a distance from the air gap of the encoder.
Other objects and advantages of the invention will be apparent in the following description, with reference to the appended drawings, in which